This invention pertains to fire closures and particularly to a fire closure system in which actuation of the closure is delayed for a preset time, measured in seconds, while the alarm system is tested or emergency generating power is brought into play, at which time the system resets itself.
Fire closures, such as fire doors, shutters, dampers, roof hatches and other devices used for fire protection of a building are activated by fusible links and/or electrical devices such as smoke detectors or fire alarm systems which are normally connected to the building's electrical systems usually served by commercial power supply sources. Electrical service is subject from time to time to failure from disability in the power network, electrical storms, high winds, falling trees and other causes. Further, from time to time fire alarm systems in the buildings are activated to insure that they are in proper working order as required by the codes and ordinances of governmental regulating agencies involved. In many systems, each time there is an electrical failure, or the system is tested, all of the fire closure devices mentioned above are activated. Consequently after the test or power outage, they must be reset to place the system back into its "stand-by" mode. This requires that maintenance personnel for the building restore all of the fire closures and the related operators to their "stand-by" condition.
This can entail a substantial number of man hours for buildings such as schools and hospitals which may have on the order of 20 to 40 fire closures. Clearly there is a substantial cost for testing each such alarm system and the switchover from commercial electrical service to an emergency power source.
Accordingly, it is a general object of this invention to provide an improved fire closure system having a mechanism to delay for an adjustable period of time, measured in seconds, the activation of the system serving to affect the fire closure while the alarm system is tested or while emergency generating power is brought into operation and which mechanism will reset itself if the alarm event or power switching event is completed within the delay period.
Another object of the invention is to provide a fail-safe release mechanism energized by electricity and responsive to fire alarm, smoke detection and other detection systems in which the release of the mechanism is delayed for an adjustable period of time measured in seconds.